Yieldable connector for the back rest of chairs



M. FOX 2952996@ CONNECTOR FOR THE BACK REST OT CHAIRS YIELDLE Filed DSG. 2l, 1946 OFFICE YTELDABLE CONNECTUR FR THE BACK REST F CHATRS Martin Fox, Chicago, lill., assigner te The Seng Company, a corporation of illinois Application Beccmber 21, 1946, Serial No. 717,681

3 Claims.

This invention relates to chairs having backrests which are movable with respect to the back frame of a chair, and more particularly to an improved connector for resiliently supporting the back-rest.

In ordinary office chairs it is common to have an arcuate back-rest movably or adjustably secured to the back frame of the chair, and for greater comfort it is preferred to have the backrest hinged to the back frame, so that it will automatically adjust itself to the back of the occupant. if the hinges are stili, automatic adjustment is impeded, and if the hinges are loose the back rest will tip forwardly each time pressure on it is released. The hinges must be designed so that their pivots are in alignment, and the hinges are often objectionable because they tend to catch and soil clothing or" the user.

The primary object of the present invention is to provide a. very simple and smooth connector which may be readily applied to the chair and will resiliently hold the back-rest in a desired position.

The invention is illustrated in preferred embodiments in the accompanying drawings in which- Fig. 1 is a side elevational View of an office chair using the improved connector; Fig. 2 is a fragmentary plan view of the chair shown in Fig. l; Fig. 3 is an enlarged fragmentary sectional view of the preferred type of connector and supporting bracket applied to a chair; Fig. 4 is a fragmentary sectional view, taken as indicated at line :ii- 41 of Fig. 3; Fig. 5 is a fragmentary sectional View, taken as indicated at line 5 5 of Fig. 3; Fig. 6, an enlarged fragmentary sectional view, showing a modied form of connector post; and Fig. '7, a fragmentary sectional view, taken as indicated at line 1l-l of Fig. 6.

In the embodiment shown in Figs. l5, an ordinary ofce chair is shown with a base 8, on which is swivelly mounted a seat 9, provided with a tilting back frame it, to which is secured an arcuate back-rest II by a pair of yieldable connector members which are the subject matter of the present invention.

Each of the connector members has a short resilient post which is formed by a heavy, helically wound steel spring I2, which is stilily resilient to lateral bending. A metal supporting bracket i3 has an outwardly struck hollow boss I4, which preferably is cut away at one side, as indicated at I5, so that one free end of the spring I2 may be secured thereto by screwing the spring into the boss, as indicated at I6. If the backrest II is made of wood, the bracket I 3 may be secured thereto by means of screws il, or if the back rest is of metal it may be bolted or welded in position.A

The other end of the spring I2 is held by a bracket I8 having a boss I9, and is shaped so that it may be secured to the back frame I0 by means of screws 2D. The boss I9 is shown open 2 at one side, so that the end of the spring may be secured to the bracket by screwing one end of the spring into the pocket formed by the boss, as indicated at 2l.

As best shown in Fig. 2, it is not necessary that the base of the brackets I3 lie in the same plane, as the resilient post will accommodate itself to the curvature of the back-rest. When the chair is occupied, the back-rest will immediately accommodate itself to the conformation of the back of the occupant, and when the chair is unoccupied, the resilient posts l2 will bring it into the position shown in Fig. l.

in the modiiication illustrated in Figs. 6 and 7, the resilient post 22 is formed of synthetic rubber, and is provided at each end with a anged head 23. The supporting brackets 2li and 25 each have outwardly struck hollow bosses which are perforated to receive the post 22 and form flanged pockets adapted to nt tightly over the flanged heads of the post and grip them to the back-rest Il and chair frame IU when the bolts lare properly tightened.

The foregoing detailed description is given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, for some modifications will be obvious to those skilled in the art.

I claim:

1. A pair of yieldable connector members for securing a back-rest resiliently to the back frame or" a chair, each of said connector members comprising: a short resilient post of stifliy elastic material, the lateral surface of said post being normally closed against admission of fabrics brought into contact therewith; and fastening brackets for each end of said post for securing it to a back-rest and back frame Which are relatively movable.

2. A device as specified in claim 1, in which the resilient post is a helically wound, fully compressed spring, and the fastening brackets each have perforate hollow bosses of sheet metal into which the free ends of said spring may be screwed.

3. A device as specified in claim l, in which the resilient post is made of rubber-like material and is provided at its ends with flanged heads, and the bracket members each have outwardly struck pockets to receive one of said flanged heads o the post and clamp it to a back member of a chair.

MARTIN FOX.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 531,165 Denio Dec. 18, 1894 1,338,854 Clark May 4, 1920 1,775,433 Krabol Sept. 9, 1930 

